Article
Physics, Applied
Zeming Sun, Zhaslan Baraissov, Ryan D. Porter, Liana Shpani, Yu-Tsun Shao, Thomas Oseroff, Michael O. Thompson, David A. Muller, Matthias U. Liepe
Summary: We demonstrate a seed-free electrochemical synthesis of Nb3Sn superconductors, which pushes the limits of their chemical and physical properties. The synthesized Nb3Sn exhibits reduced surface roughness, improved stoichiometry, and minimized impurity concentrations compared to conventional methods. The application of this Nb3Sn in large-scale 1.3 GHz SRF cavities shows the potential for high efficiency and high fields.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
Ziqin Yang, Shichun Huang, Yuan He, Xiangyang Lu, Hao Guo, Chunlong Li, Xiaofei Niu, Pingran Xiong, Yukun Song, Andong Wu, Bin Xie, Zhiming You, Qingwei Chu, Teng Tan, Feng Pan, Ming Lu, Didi Luo, Junhui Zhang, Shenghu Zhang, Wenlong Zhan
Summary: The study demonstrates that low temperature baking significantly improves the performance of Nb3Sn thin film cavities, increasing Q (0) by about 8 times in the intermediate field region and further improving by approximately 20% under better test conditions.
CHINESE PHYSICS LETTERS
(2021)
Article
Physics, Applied
Zeming Sun, Zhaslan Baraissov, Catherine A. Dukes, Darrah K. Dare, Thomas Oseroff, Michael O. Thompson, David A. Muller, Matthias U. Liepe
Summary: The surface compositions, structural profiles, and valence distributions of niobium and niobium-tin under different processing conditions were investigated. It was found that carbide formation during high-temperature baking determines subsequent oxide formation, which has important implications for ultra-high vacuum baking and nitrogen processing. Additionally, vapor-diffused Nb3Sn contains thick metastable oxides, while electrochemically synthesized Nb3Sn only has a thin oxide layer.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
S. Aliasghari, E. Avcu, P. Skeldon, R. Valizadeh, B. Mingo
Summary: This study presents the first investigation into the abrasion resistance and degradation processes of magnetron-sputtered Nb3Sn coatings on electropolished or chemical polished copper substrates. The findings reveal different stages of coating damage and indicate similar abrasion resistance behavior for both substrate conditions.
MATERIALS & DESIGN
(2023)
Article
Computer Science, Information Systems
Waqas Ahmed Toor, Muhammad Ashraf
Summary: The use of Disturbance Observer-based (DOB) control is widespread in stabilizing the electromagnetic field in superconducting radio frequency cavities to facilitate beam acceleration in particle accelerators. Repetitive disturbances such as beam loading and cavity detuning are compensated by DOB control, and their suppression is enhanced through the incorporation of a learning scheme into the conventional disturbance observer. This paper evaluates the performance of a learning-based disturbance observer for compensating beam loading and cavity detuning in pulsed superconducting radio frequency cavities and proposes modifications for better field stability. The simulation results show that the learning-based disturbance observer yields faster convergence to the reference input and lower tracking errors during the flat top of pulse voltage in comparison to conventional disturbance observer control.
Article
Instruments & Instrumentation
Akhilesh Jain, Deepak Kumar Sharma, Alok Kumar Gupta, Kriti Pathak, M. R. Lad
Summary: A high-power solid-state radio frequency amplifier facility has been established at the Raja Ramanna Centre for Advanced Technology for testing superconducting radio frequency dressed cavities. With a maximum output power of 36 kW, its main features include a modular and scalable design, with components such as 500 W, 20 dB gain modules and novel dividers. The efficiency and performance of the amplifier and its constituent components have been rigorously tested and confirmed.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Multidisciplinary Sciences
Chris Sundahl, Junki Makita, Paul B. Welander, Yi-Feng Su, Fumitake Kametani, Lin Xie, Huimin Zhang, Lian Li, Alex Gurevich, Chang-Beom Eom
Summary: This research reports the growth and characterization of Nb3Sn/Al2O3 multilayer structures with good superconducting and RF properties, providing a materials platform for the development and optimization of high-performance SIS multilayers.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Industrial
A. Camelin, P. Naisson, G. Poulachon, A. D'Acunto, S. Atieh
Summary: This study focuses on the machining process of oxygen-free electronic (OFE) copper. It investigates the cutting forces and thermal load on the tool during finish turning, and evaluates the surface integrity through advanced microstructural analysis. Optimal cutting conditions are defined and confirmed through metallurgical analysis.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Yoshimitsu Hishinuma, Akihiro Kikuchi, Hidetoshi Oguro, Hiroyasu Taniguchi, Satoshi Awaji, Takeo Muroga
Summary: This paper reviews the high mechanical strengthened Nb3Sn superconducting wires with various reinforcing materials and proposes a new high mechanical strength method without reinforcing material. Commercial-like internal matrix reinforced Nb3Sn superconducting multifilamentary wires were successfully fabricated, and their superconducting properties and mechanical strength were discussed.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Physics, Multidisciplinary
A. Romanenko, R. Harnik, A. R. Grassellino, R. Pilipenko, Y. Pischalnikov, Z. Liu, O. S. Melnychuk, B. Giaccone, O. Pronitchev, T. Khabiboulline, D. Frolov, S. Belomestnykh, A. Berlin, A. Hook
Summary: The study conducts the first light-shining-through-wall (LSW) search for dark photons using high-quality-factor superconducting radio frequency (SRF) cavities called Dark SRF. They establish a new exclusion limit and provide the world's best constraints on dark photons. This research serves as a proof of concept for the role of SRF cavities in LSW setups.
PHYSICAL REVIEW LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Takanori Fujita, Naoto Sekiya
Summary: The research team designed the first superconducting bulk coil for radio frequency applications and investigated the impact of line gap and line width on the coil's quality factor through simulations. Despite being non-optimized, the quality factor of the superconducting bulk coil was three times higher than that of a copper coil in test samples.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2021)
Article
Physics, Applied
S. Posen, J. Lee, D. N. Seidman, A. Romanenko, B. Tennis, O. S. Melnychuk, D. A. Sergatskov
Summary: Nb3Sn is a promising material for superconducting radiofrequency cavities, showing potential for higher accelerating fields and industrial accelerator applications. New results include higher field strengths in single cell cavities and the first Nb3Sn-coated 9-cell cavity demonstration. The study reveals smooth surfaces, reduced film thickness, and implications for RF superconductivity physics.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2021)
Article
Optics
Vakhtang Jandieri, Ramaz Khomeriki, Koki Watanabe, Daniel Erni, Douglas H. Werner, Jamal Berakdar
Summary: Realization of externally tunable chiral photonic sources and resonators using oxide-based stacks of helical multiferroic layers, provides a suitable, electrically-controllable medium to efficiently trap and filter purely chiral photonic fields.
Article
Engineering, Multidisciplinary
N. A. Stilin, A. Holic, M. Liepe, R. D. Porter, J. Sears, Z. Sun
Summary: Development of Nb3Sn coatings has enabled efficient RF operation at 4.2 K, making it possible to use cryocoolers instead of liquid helium for cooling SRF cavities. This eliminates the need for expensive cryogenic infrastructure, making SRF technology accessible to small-scale applications. Cornell University has developed a new cavity testing assembly using a Cryomech PT420-RM cryocooler to cool a 2.6 GHz Nb3Sn cavity, achieving breakthrough performance in conduction cooled cavities. The findings provide guidance for designing a cryocooler-based cryomodule for beam energy gains.
ENGINEERING RESEARCH EXPRESS
(2023)
Article
Engineering, Electrical & Electronic
Hongjuan Zheng, Pei Zhang, Zhongquan Li, Qiang Ma, Zhenghui Mi, Xinying Zhang, Tongming Huang, Ruixiong Han, Changcheng Ma, Rui Ge, Weimin Pan
Summary: The proposed 499.8-MHz superconducting cavities for HEPS are designed to provide 3.5-MV RF voltage and 400 kW of beam power, enabling a complex RF gymnastics for a novel injection scheme. The cavity design focuses on optimizing mechanical properties, including investigating various wall thicknesses and external stiffening mechanisms. Extensive design optimizations have been conducted to improve stress, buckling pressure, and frequencies of mechanical modes, while monitoring frequency tunability, pressure sensitivity, and Lorentz force detuning to ensure compliance.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2021)
Article
Electrochemistry
Laura Holtschi, Camelia N. Borca, Thomas Huthwelker, Federica Marone, Christian M. Schlepuetz, Vincent Pele, Christian Jordy, Claire Villevieille, Mario El Kazzi, Petr Novak
Summary: A suite of analytical techniques were applied to investigate the limitations of fast cycling in composite graphite electrodes in all-solid-state cells with sulfide electrolytes, identifying cracks in the electrodes, poor percolation of conducting particles, and the formation of compounds increasing the interfacial resistance. Despite kinetic limitations, excellent long-term cycling performance was demonstrated at specific rates, suggesting slow self-passivation processes at the interface.
ELECTROCHIMICA ACTA
(2021)
Article
Biology
Isabelle P. Maiditsch, Friedrich Ladich, Martin Hess, Christian M. Schlepuetz, Tanja Schulz-Mirbach
Summary: This study aimed to develop a new approach to non-invasively study the motion of fish auditory structures. By designing a miniature standing wave tube-like setup, the motion of otoliths and auditory structures in zebrafish and glass catfish was successfully visualized.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Article
Optics
Zhitian Shi, Daniel Josell, Konstantins Jefimovs, Lucia Romano, Thomas P. Moffat, Marco Stampanoni, Christian M. Schleputz
Summary: This study proposes a device with a fractal pattern for precise automatic focusing in high-resolution X-ray tomography. The device generates X-ray transmission images with globally homogeneous macroscopic visibility and high local contrast, and can be used for different pixel sizes and X-ray energies.
Article
Chemistry, Physical
Robert Fischer, Christian M. Schlepuetz, Jianlin Zhao, Pierre Boillat, Dirk Hegemann, Rene M. Rossi, Dominique Derome, Jan Carmeliet
Summary: The wicking dynamics in yarns are not solely determined by inter-fiber pore filling, but are mainly influenced by the transition processes between pores and the structure of the pore network. The yarn pore system consists of a sparse network of long and narrow pores, which leads to step-wise wicking dynamics with fast pore filling events and long waiting times between filling events.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Physics, Nuclear
S. Posen, A. Cravatta, M. Checchin, S. Aderhold, C. Adolphsen, T. Arkan, D. Bafia, A. Benwell, D. Bice, B. Chase, C. Contreras-Martinez, L. Doolittle, J. Fuerst, D. Gonnella, A. Grassellino, C. Grimm, B. Hansen, E. Harms, B. Hartsell, G. Hays, J. Holzbauer, S. Hoobler, J. Kaluzny, T. Khabiboulline, M. Kucera, D. Lambert, R. Legg, F. Lewis, J. Makara, H. Maniar, J. T. Maniscalco, M. Martinello, J. Nelson, S. Paiagua, Y. Pischalnikov, P. Prieto, J. Reid, M. Ross, C. Serrano, N. Solyak, A. Syed, D. Sun, G. Tatkowski, R. Wang, M. White, L. Zacarias
Summary: A novel high energy cryomodule was tested at Fermilab, demonstrating excellent performance exceeding specifications by improving gradient performance and addressing sporadic quenches issues.
PHYSICAL REVIEW ACCELERATORS AND BEAMS
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Alexandra Migga, Georg Schulz, Griffin Rodgers, Melissa Osterwalder, Christine Tanner, Holger Blank, Iwan Jerjen, Phil Salmon, William Twengstrom, Mario Scheel, Timm Weitkamp, Christian M. Schleputz, Jan S. Bolten, Jorg Huwyler, Gerhard Hotz, Srinivas Madduri, Bert Muller
Summary: By comparing the performance of three cutting-edge laboratory tomography systems, it was found that next-generation laboratory-based microtomography almost reached the quality achieved by synchrotron facilities, allowing successful visualization of medically relevant microanatomical features.
JOURNAL OF MEDICAL IMAGING
(2022)
Article
Engineering, Chemical
Vladimir Novak, Miroslav Blazek, Christian M. Schleputz, Petr Koci, Marco Stampanoni
Summary: In this study, time-resolved X-ray tomography was used to investigate the drying of water in porous ceramic substrates. The study achieved a time resolution of 2 seconds and utilized machine learning-based image processing to track pore emptying and filling. The drying curves obtained from the tomographic data revealed the drying process in materials with different structural properties. The study also observed the effects of water redistribution and rapid pore emptying on drying dynamics.
Article
Chemistry, Physical
Robert Fischer, Christian M. Schleputz, Rene M. Rossi, Dominique Derome, Jan Carmeliet
Summary: The wicking flow in knit fabrics is slowed by capillary pressure minima during the transition at yarn contacts due to the characteristic pore structure of yarns. Experimental and modeling studies were conducted to investigate the water configuration evolution and the delay times for pore intrusion. The findings reveal that the water advance is slow in the thin interface zone at the yarn contact and a deep capillary pressure minimum occurs, effectively delaying the wicking flow. The pore network model successfully reproduces the observed wicking dynamics, including inter-yarn wicking.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Physics, Nuclear
B. Giaccone, P. Berrutti, M. Martinello, S. Posen, A. Cravatta, A. Netepenko, T. Arkan, A. Grassellino, B. Hartsell, J. Kaluzny, A. Penhollow, D. Gonnella, M. Ross, J. Fuerst, G. Hays, J. T. Maniscalco, M. Doleans
Summary: This article presents the application of plasma cleaning technique in superconducting radio-frequency cavities to reduce field emission and multipacting issues. The results show that plasma processing preserves cavity performance and eliminates contaminants, offering potential benefits for cryomodule testing and linac commissioning.
PHYSICAL REVIEW ACCELERATORS AND BEAMS
(2022)
Article
Engineering, Electrical & Electronic
R. Kostin, C. Jing, S. Posen, T. Khabiboulline, D. Bice
Summary: RF (SRF) photoguns are emerging as promising candidates for Ultra fast Electron Diffraction/Microscopy (EUD/UEM) applications due to their ultrahigh shot-to-shot stability compared to room temperature RF photoguns. Recent advancements in Nb3Sn and conduction cooling have made SRF technology more affordable for industrial use. Euclid is developing a 1.3 GHz, continuous wave (CW), 1.5-cell, MeV-scale SRF conduction cooled photogun and this paper presents the first high power results of the gun covered with Nb3Sn.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2023)
Article
Engineering, Electrical & Electronic
E. Viklund, J. Lee, D. N. Seidman, S. Posen
Summary: Niobium has been the preferred material for SRF cavities, but its accelerating gradient is reaching its limit. Nb3Sn is a potential alternative with higher superconducting properties, but its brittleness hinders cavity formation. This study analyzes the 3-D structure of Nb3Sn films using focused ion beam tomography and reveals tin-deficient regions near the surface.
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2023)
Article
Cell Biology
Sanja Blaskovic, Pinelopi Anagnostopoulou, Elena Borisova, Dominik Schittny, Yves Donati, David Haberthur, Zhe Zhou-Suckow, Marcus A. Mall, Christian M. Schleputz, Marco Stampanoni, Constance Barazzone-Argiroffo, Johannes C. Schittny
Summary: This study developed a new pipeline for analyzing all airspaces of the entire lung. The results demonstrated irregular widening of parenchymal airspaces in mice with cystic fibrosis-like lung disease and elastase-induced emphysema. The pipeline showed applicability to different imaging modalities and is suitable for studying structural alterations in chronic obstructive lung diseases.
Article
Materials Science, Multidisciplinary
Malgorzata G. Makowska, Fabrizio Verga, Stefan Pfeiffer, Federica Marone, Cynthia S. T. Chang, Kevin Florio, Christian M. Schleputz, Konrad Wegener, Thomas Graule, Steven Van Petegem
Summary: Laser-based Powder Bed Fusion (LPBF) of oxide ceramics allows for fabrication of complex three-dimensional objects, but the mechanical properties of dense LPBF-manufactured ceramics are poor due to structural defects. In this study, operando tomographic microscopy is used to investigate the effects of laser energy density on surface roughness, powder denudation zone, and porosity formation mechanisms. The findings show that increasing laser power results in wider melt pools without affecting their depth, and that increasing power can both eliminate fusion porosity and enhance the formation of spherical porosity.
COMMUNICATIONS MATERIALS
(2023)
Article
Respiratory System
Sanja Blaskovic, Yves Donati, Isabelle Ruchonnet-Metrailler, Yannick Avila, Dominik Schittny, Christian Matthias Schleputz, Johannes Constantin Schittny, Constance Barazzone-Argiroffo
Summary: This study focuses on the impact of early life nicotine exposure on adult lung functions and elastase-induced emphysema, showing no effect of nicotine on lung functions but potential influence on immune system response in emphysema.
RESPIRATORY RESEARCH
(2022)
Article
Physics, Fluids & Plasmas
Robert Fischer, Christian M. Schlepuetz, Dirk Hegemann, Rene M. Rossi, Dominique Derome, Jan Carmeliet
Summary: The mechanisms of spontaneous imbibition dynamics in polyethylene terephthalate filament yarns at pore scale are complex and may not follow traditional laws such as Washburn's law. The stepwise dynamics observed in yarns is a result of the interplay between thermodynamic free energy and viscous dissipation. Time-resolved synchrotron x-ray microtomography reveals fast pore-filling events separated by long periods of low flux in yarns.
